relationship between two numerical variables
DESCRIPTION
Relationship between Two Numerical Variables. By Farrokh Alemi, Ph.D. Relationships. Investigators are often interested in relationship between variables. Anecdotal Data. Multiple observations needed. Anecdotal Data. I have smoked all my life and I do not have cancer. Relationships. - PowerPoint PPT PresentationTRANSCRIPT
RELATIONSHIP BETWEEN TWO NUMERICAL VARIABLES
By Farrokh Alemi, Ph.D.
Investigators are often interested in relationship between variables
Relationships
Multiple observations needed
Anecdotal Data
I have smoked all my life and I do not have cancer
Anecdotal Data
Relationships
Independent X & Y
Explanatory Variable𝐸𝑥𝑝𝑙𝑎𝑛𝑎𝑡𝑜𝑟𝑦 𝑣𝑎𝑟𝑖𝑎𝑏𝑙𝑒 𝑚𝑖𝑔ℎ𝑡 𝑎𝑓𝑓𝑒𝑐𝑡
ሱۛ ۛ ۛ ۛ ۛ ۛ ۛ ۛ ሮ 𝑅𝑒𝑠𝑝𝑜𝑛𝑠𝑒
Association Is Not Causation
Causation Requires: Association Sequence (causes preceded effects) Mechanism Counter factual (no effect when causes
are absent)
Causation Requires: Association Sequence (causes preceded effects) Mechanism Counter factual (no effect when causes
are absent)
Causation Requires: Association Sequence (causes preceded effects) Mechanism Counter factual (no effect when causes
are absent)
Causation Requires: Association Sequence (causes preceded effects) Mechanism Counter factual (no effect when causes
are absent)
Association Is Not Causation
A Scatterplot can show the association between two variables
Take Home Message
Do one: